Electronic Modulation of MnOx Nanoclusters via Atomically Incorporated Co for Enhanced Oxidative Dehydrogenation of 1-Phenylethanol

Alumina-supported manganese oxide nanocluster catalysts doped with various 3d transition metals (Fe, Co, Ni, and Cu) were prepared via a colloidal method using polyvinyl alcohol as a stabilizer. High-angle annular dark-field scanning transmission electron microscopy observation confirmed the homogeneous dispersion of the dopants within the MnOx nanoclusters on the Al2O3 support. Among the dopants investigated, the cobalt-doped catalyst exhibited the highest catalytic activity for the oxidative dehydrogenation of 1-phenylethanol. X-ray absorption fine structure analysis revealed that the addition of cobalt alters the valence state of manganese, which is considered the primary factor driving the enhanced catalytic performance.